What are several parameters mean in fvSolution file?

renyun0511 · September 20, 2012, 00:31

Hi,
I'm using OpenFOAM-1.5-dev,and confusing with the parameters in fvSolution.
firstly, what are the meaning of "relTol" and "tolerance"? and are they differences? how to set by commonly?
secondly, what is the meaning of "nCellsInCoarsestLevel"? the mesh is better, and the value of "nCellsInCoarsestLevel" is less ?

Thanks
Best Regards!

Yun Ren

chegdan · September 20, 2012, 12:54

This is briefly covered in the User Guide, but

tolerance
When value of the residual in the linear system solver that is scaled using the definition here falls below tolerance, it will stop the linear system solver.

relTol
When the value of the ratio of the current residual over the initial residual (where the initial residual has been scaled using the above procedure) falls below relTol, the linear system solver will stop.

nCellsInCoarsestLevel
start with ncellsincoarsestlevel

Hope this helps.

September 20, 2012, 00:31	What are several parameters mean in fvSolution file?	#1
renyun0511 Member 任芸 Join Date: Jun 2009 Posts: 75 Rep Power: 17	Hi, I'm using OpenFOAM-1.5-dev,and confusing with the parameters in fvSolution. firstly, what are the meaning of "relTol" and "tolerance"? and are they differences? how to set by commonly? secondly, what is the meaning of "nCellsInCoarsestLevel"? the mesh is better, and the value of "nCellsInCoarsestLevel" is less ? Thanks Best Regards! Yun Ren

September 20, 2012, 12:54		#2
chegdan Senior Member Daniel P. Combest Join Date: Mar 2009 Location: St. Louis, USA Posts: 621 Rep Power: 0	This is briefly covered in the User Guide, but tolerance When value of the residual in the linear system solver that is scaled using the definition here falls below tolerance, it will stop the linear system solver. relTol When the value of the ratio of the current residual over the initial residual (where the initial residual has been scaled using the above procedure) falls below relTol, the linear system solver will stop. nCellsInCoarsestLevel start with ncellsincoarsestlevel Hope this helps. siamak 60 likes this.

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